Renée Zellwegger as Bridget Jones: Is diary writing destined to be hidden under the covers? (Picture: Universal)

‘Dear Diary,Had an awful day today. My mum and dad made me go to bed after Wogan was over (it was still light outside!) and I also broke my Optimus Prime figure. I hate the world. Can’t wait to watch Ninja Turtles tomorrow after school though! Night night!’

I didn’t keep a regular diary in my youth, but if I had, it might have contained an entry that went a little like the above.

Dairies have a long and illustrious history, which can be traced through Samuel Pepys to Bridget Jones. In the hands of a hormonal teenager, however, they wield a power far greater than any parent could possibly imagine. Reading someone else’s diary without their knowledge was an unforgiveable act, for the messy melding of ink and paper within opened a window into a person’s soul. Or, you know, detailed what boys in school they wanted to kiss.

There is an assumption that we take more care over something if we physically write it, but are diaries or journals really more worthy than the musings we make on Twitter, Facebook, WordPress, Tumblr, Medium or Blogger? Perhaps not – Pepys’ diary, written in the 1660s, is now available in bite-sized 140-character tweets. Had he written it 350 years later than he did, it would almost certainly have found a home online.

A diary lets us put who we are on to paper, but it also allows us to describe who we want to be. Even when they are mundane, there is something aspirational about them. And they are also good for us. New research from the University of Minnesota shows that workers who write down the day’s events in the office lowered their stress levels. Diaries have long been cited as a key component for those attempting to quit smoking. In a study by the University of California in 2009, brain scans of diary writers showed they were less prone to emotional problems.

Professor Theresa Glomb, who helped carry out the study at the University of Minnesota, said: ‘At the end of the work day, we asked employees to write three good things that happened and why. This brief positive refocusing intervention had beneficial effects on perceived stress, blood pressure, physical symptoms, mental health and work detachment.

‘I do think that blogs and other social media make it easier to capture, record, and reflect on one’s experience, so that may drive people to practice reflection. However, I do think it is rather different from the old-fashioned act of writing a diary. Unlike a blog, a written diary is typically not for public consumption – it’s just for you – and so you need not censor your thoughts or what you document. ‘

Earlier this month, actress Sheila Hancock revealed she had burnt the diaries she used to write her memoirs – she said she didn’t want to cause hurt to family members. Rae Earl, the author of My Mad, Fat Teenage Diary, backed the move, calling private journals ‘dangerous and emotionally loaded’. Still, that doesn’t stop us from keeping them, even against the lure of setting up a blog. A survey conducted at the beginning of this year to coincide with the launch of the TV version of Earl’s book, revealed that eight out of ten teenage girls have a written diary.

It’s not just teenagers who keep them, however. And it’s not just girls.

Dane Cobain, a 24-year-old social media marketer, writer and musician from High Wycombe, Buckinghamshire, is coming to the end of his eleventh physical diary – he has been writing a journal for the past seven years, taking 15 minutes out of every day to do so. He estimates that he has written about 600,000 words on his adult life.

‘It’s actually the only thing I still write by hand, just because it somehow feels more natural,’ he explained, although he also types up his journal afterwards to keep a computer record.

‘You develop an attachment to the diaries and writing by hand feels more personal than bashing away at a keyboard,’ he said.

Cobain says his diary helps him make sense of the events in his life. ‘It’s kind of like being able to look back on a confusing situation and to be able to see it all clearly, but on a much more rapid and a much smaller scale.’

For him, events – not feelings – make up the content. ‘It’s probably better that way as well, I don’t want to be some bitter loner writing alone in his room about how much he hates everyone!’

However, he admits it has changed from when he started at 17.

‘It used to be a lot more angsty, but I mellowed out as I got a bit older and now it’s much more relaxed.’

Mignon Fogarty, the creator of the Grammar Girl website and podcast in the US, kept a diary in school and university.

‘I find the college diaries slightly more interesting, but mostly just because they reveal what a clueless git I was,’ she said.

Her diary writing days ended when the journal went missing.

‘I lost a diary – or had it stolen – in college, and I never quite got over it,’ she said. ‘Knowing that someone is reading your most private thoughts is like a knife in the gut. I haven’t been able to keep a diary since.’

She said a private journal lets the writer explore their feelings in a deep way, something that the public platform of a blog doesn’t always allow.

She warned, however, that even after you’re gone, your diary has a power all of its own to cause pain to others.

‘Having gone through my parents’ belongings after they died, I always imagine someone finding my diaries after I’m gone, so it never feels truly private. I think those are the biggest risks if you write personal entries – that you will be hurt if the diary isn’t secure or, perhaps worse, something you wrote, perhaps just exploring an idea or feeling, will hurt someone you love after you die. I met a woman once who had kept diaries her whole life, but kept them in a locked safe and had convinced a friend to destroy them all without reading them when she died.’

Francesca De Franco, 34, from London, who runs The Parent Social website, kept a diary when pregnant with her first child in 2008 and did so again when pregnant with twins three years later. She intends to hand the diaries over to her three daughters when they reach 18.

‘I found it quite cathartic,’ she said. ‘It was a channel for writing not only about events in the pregnancy, but also about my many worries and neuroses. I was aware that I was probably boring my husband, so it was good to write down what I was feeling instead. It also helped me to gain some perspective.

‘I did have diaries when I was younger. They mainly contained stuff about which friends weren’t talking to which, the boys I fancied and how much my boobs had grown – or which outfits showed them off to best effect – the things that were obviously important to me at the time!’

Dr Irving Finkel, a curator in the Department of the Middle East at the British Museum, has been rescuing unwanted diaries for the past eight years and has amassed more than 1,000, which are set to become available to researchers and the public through the Great Diary Project, aiming to be installed at the Bishopsgate Institute in London in the near future.

Most of Dr Finkel’s diaries date from the first half of the 20th or second half of the 19th century.

‘As long as people write diaries and as long as there are examples around, they ought to be rescued,’ he said.

‘Lots of people talk about the weather and absolutely mundane things like washing their hair and cutting the lawn – some diaries are full of that stuff. Then something happens, they meet someone, there’s an adventure and you suddenly find whenever you peep into people’s lives that nobody has a completely normal mundane life – nobody does.’

He added: ‘The diary itself is a very fascinating thing. Lots of people use a diary as a sort of confessional, as an intimate friend. Sometimes people pore out their inner thoughts, they fill up the whole of Tuesday and go into Wednesday when they’re not supposed to and then go down the margin with a little balloon – you can see when people are happy or distressed or worried in their handwriting. ‘It’s not always great poetry or great literature but what it really is, is great experience. When people use a diary as a record, they always write down what from their point of view is the truth of the situation – they don’t make things up. They don’t distort events. They don’t pretend things happened or didn’t – there’s no point because it’s really only you that’s ever going to read it.’

He insists that saving old diaries for future generations to study is important.

‘We live in a time that is so complex and so noisy and also changing so rapidly that it’s quite impossible to imagine what things will be like in 100 years,’ he said. ‘If we had rooms and rooms of these little books, they would be something real from that time.’

While Dr Finkel fears diaries will die out, online equivalents can never match their intimacy.

‘If you write a real diary about your life, the last thing you want is anybody else to read it,’ he said. ‘People go to a lot of trouble to hide them. Whereas if you write a blog your private plan is that 50m people read about your dirty laundry. You can’t say that the blog is a replacement for the diary.’